[BD-53] Video and Unit Skill Tagging

Executive Summary:

In order to speed the development of a new generation of skills-based edX experiences, the Enterprise Theme proposes engaging a blended provider to help us tag all 800K~ course units and up to 1M unique videos with skills tags we can use to better build experiences that measure and model what learners are learning on edX, with the project being implemented with an external provider and managed by the Markhors engineering team.

The end goal is to compete directly with experiences we are seeing come out of Coursera, Pluralsight and other competitors, and strengthen our product marketing narrative of edX as an upskilling platform.